1. Field of the Invention
The present invention relates generally to fluid actuated connectors, and in particular to fluid connectors used in connecting printed circuit cards to printed circuit boards, such as a motherboard, the like capable of use in a computer product, such as a personal or mainframe computer.
2. Description of Related Art
Fluid actuated electrical connectors are well known in the art for providing force between contacts to allow for electrical connection. For example, U.S. Pat. No. 3,594,707 describes a fluid pocket with a flexible conductor supporting material having an insert strip conductor bonded thereto. The conductor supporting material expands in response to fluid pressure and provides contact between the insert strip and a spring connector. U.S. Pat. Nos. 2,956,258; 3,076,166; and 3,090,026 all describe a discrete fluid filled flexible bag, actuated by a screw compression device, which expands and contacts printed circuit cards, thereby forcing them into an electrically connecting relationship. U.S. Pat. No. 4,220,389 discusses a zero insertion force connector wherein an expandable tube runs parallel with contact surfaces and relieves the tension of a contact spring when expanded, thereby allowing a circuit card to be inserted into the connector. Upon deflation of the tube, the spring biases the contact surfaces towards the card making an electrical connection therebetween. U.S. Pat. No. 4,968,265 also describes various configurations utilizing discrete bladders and expandable tubes to effect connections between electrical contacts. Another U.S. Pat. No. 2,978,666 utilizes a flexible tube, doubled in half, thereby forming two parallel legs, having a row of contacts in between. A circuit card is then inserted intermediate the contacts and the tube is expanded which constrains the contacts against conductor strips of the printed circuit card. Finally. U.S. Pat. No. 2,636,068 and German Patent DE 3621064 A1 show connectors using a flexible bladder like member to effect electrical connection between contacts.
It can be seen that each of these references utilize a discrete component which is used to force an adjacent contact into an electrically contacting relation with another contact, circuit card, or the like. Conversely, none of the above cited art shows a single electrical/mechanical element which not only responds to fluctuations in fluid pressure, but also exhibits the electrical characteristics which match the printed circuit card being connected, i.e. controlled characteristic impedance, noise coupling coefficient, independent power connections with low inductance, etc.
Further, from a manufacturing point of view, it would be desirable to be able to fabricate this electrical circuit element membrane at the same time and with the same processes as the circuit card being inserted into the connector. Additionally, it would also be advantageous to eliminate the need for a mechanical element, e.g. discrete bladder, to provide force to a separate electrical element. The elimination of a component of the connector and the problems associated with manufacturing, and maintaining the mechanical element under pressure will provide a more reliable connector system. By elimination of the mechanical element a more uniform pressure is brought to bear on the electrical element, since a resilient layer between the pressurized fluid and the electrical contact being displaced is removed.
For these reasons, it can be seen how a single resilient electrical membrane utilized in a fluid connector is desirable.